Are my guages fubar'd?

[wavestarved]

Hey all,
just got round to replacing my fire extinguisher C02 with a proper cylinder. Both of these were sold as full and came with the appropriate seals but when rigged up to my regulator the pressure guage barely registers.
With the fire extinguisher C02 it only registered just above the red, with the larger bottle it doesn't even get out of the red, in fact the needle only moves a couple of mm. The flow rate meter seems to be working just fine and there is deffinitely plenty of gas in both cylinders, does this mean that the regulator is at fault? Does the reg need setting up somehow?
It was only purchased brand new a couple of weeks back, but I'm sure there'll be no probs taking it back if it's knacked. Any advice welcomed.
Cheers

 

[pedrobedro]

CO2 is sold as a liquid by weight in the cylinder and only the space above the liquid is gas so the pressure does not read very high. In the cold it will read even less, try taking your cylinder into the house and notice if it rises. The gauges are standard to read gas under pressure up to 300 bar so they hardly register the CO2 pressure.

 

[Country Joe]

Hi there,
I think it's to do with the gas being stored as a liquid.
Maybe the difference is that the new cylinder is very full of liquid co2, so theres not that much space above it for the pressurised gas, giving an even lower reading than you'd expect - even with co2?
How's that for a badly-explained thought?
I suppose I'm saying I'd keep the reg, I bet it's fine.
All the Best,
CJ

Oh yeah, and what Pedro says too.
But he hadn't said it when I started rambling!

 

[cumbriasteve]

My C02 reads nearly empty but is 85% full at least, don't worry, both previous posts are spot on with their advice

 

[shenion]

Should read teh same regardless how full it is. CO2 does seem to vary more with temperature.

 

[rtbcomp]

As above, but CO2 drops off very quickly once the liquid has boiled off, so you don't get much warning that you're going to run out of gas.

 

[wavestarved]

Wow excellent responses and explanations; I bet if I re hook the fire extinguisher it'll read even less than before then, being so damned cold.
Thanks all very much, I am enlightened and relieved.

 

[eil]

Weigh the bottle on bathroom scales, then subtract the tare weight of the bottle, then you will know how much liquid you have in them. the tare is normally stamped around the top of the cylinder.

 

[wavestarved]

Weigh the bottle on bathroom scales, then subtract the tare weight of the bottle, then you will know how much liquid you have in them. the tare is normally stamped around the top of the cylinder.

Good idea but I have no bathroom scales, they're banned from my house. Might look a bit odd carrying what looks like a WW2 bomb into Boots to get it weighed. :